Measuring and Evaluating a Test Signal Generated by a Device Under Test (DUT)

ABSTRACT

Embodiments described herein generally relate to measuring and evaluating a test signal generated by a device under test (DUT). In particular, the test signal generated by the DUT may be compared to a reference signal and scored based on the comparison. For example, a method may include: capturing a test signal from a device under test; splicing the test signal into a plurality of test audio files based on a plurality of frequency bins; at each frequency bin, comparing each of the plurality of test audio files to a corresponding reference audio file from among a plurality of reference audio files, the plurality of reference audio files being associated with a reference signal; and calculating a performance score of the device under test based on the comparisons.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/662,785, filed Oct. 24, 2019, now pending, which is incorporatedherein by reference in its entirety.

TECHNICAL FIELD

Embodiments included herein generally relate to measuring and evaluatinga test signal generated by a device under test (DUT). In particular, thetest signal generated by the DUT may be compared to a reference signaland scored based on the comparison.

BACKGROUND

An ideal acoustic signal may be represented by a sinusoidal wave havinga smooth curve in the time domain and have a single peak at thefundamental frequency in the spectral domain. However, in practicalsettings, acoustic signals output by speakers frequently are imperfectsinusoidal waves with jagged, bent, and unexpected waveforms in the timedomain and multiple peaks (i.e., overtones) at frequencies other thanthe fundamental frequency. Testing these speakers to gauge their qualityoften requires a human listener to vet the quality of the speaker, andas such, the quality of the speaker may not be quantifiable.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are incorporated herein and form a part of thespecification.

FIG. 1 illustrates a testing environment, according to some embodiments.

FIG. 2 illustrates a speaker, according to some embodiments.

FIG. 3 illustrates a flowchart for measuring and evaluating a signalgenerated by a device under test (DUT), according to some embodiments.

FIG. 4 illustrates an example computer system useful for implementingvarious embodiments.

FIGS. 5A-5B illustrate time domain and spectral domain performances,respectively, of an ideal speaker, according to some embodiments.

FIGS. 6A-6B illustrate time domain and spectral domain performances,respectively, of a reference speaker, according to some embodiments.

FIGS. 6C-6D illustrate time domain and spectral domain performances,respectively, of another speaker, according to some embodiments.

FIGS. 7-9 illustrate performance graphs of a device under test (DUT),according to some embodiments.

In the drawings, like reference numbers generally indicate identical orsimilar elements. Additionally, generally, the left-most digit(s) of areference number identifies the drawing in which the reference numberfirst appears.

SUMMARY

Provided herein are system, apparatus, article of manufacture, methodand/or computer program product embodiments, and/or combinations andsub-combinations thereof, for measuring and evaluating a signalgenerated by a device under test (DUT).

In some embodiments, the present disclosure is directed to a method formeasuring and evaluating a signal generated by a device under test(DUT). The method may include: capturing a test signal from a deviceunder test; splicing the test signal into a plurality of test audiofiles based on a plurality of frequency bins; at each frequency bin,comparing each of the plurality of test audio files to a correspondingreference audio file from among a plurality of reference audio files,the plurality of reference audio files being associated with a referencesignal; and calculating a performance score of the device under testbased on the comparisons.

In some embodiments, the present disclosure is directed to anon-transitory, tangible computer-readable device having instructionsstored thereon that, when executed by at least one computing device,causes the at least one computing device to perform operations. Theoperations may include: capturing a test signal from a device undertest; splicing the test signal into a plurality of test audio filesbased on a plurality of frequency bins; at each frequency bin, comparingeach of the plurality of test audio files to a corresponding referenceaudio file from among a plurality of reference audio files, theplurality of reference audio files being associated with a referencesignal; and calculating a performance score of the device under testbased on the comparisons.

In some embodiments, the present disclosure is directed to a device. Thedevice may include a memory storing instructions for measuring andevaluating a signal generated by a device under test (DUT) and aprocessor configured to execute the instructions. The instructions maycause the processor to perform operations including: capturing a testsignal from the DUT; slicing the test signal into a plurality of testaudio files based on a plurality of frequency bins; at each frequencybin, comparing each of the plurality of test audio files to acorresponding reference audio file from among a plurality of referenceaudio files, the plurality of reference audio files being associatedwith a reference signal, and calculating a performance score of thedevice under test based on the comparisons.

Further features and advantages of the embodiments disclosed herein, aswell as the structure and operation of various embodiments, aredescribed in details below with reference to the accompanying drawings.It is noted that this disclosure is not limited to the specificembodiments described herein. Such embodiments are presented herein forillustrative purposes only. Additional embodiments will be apparent to aperson skilled in the relevant art based on the teachings containedherein.

DETAILED DESCRIPTION OF THE INVENTION

Provided herein are system, method, computer program product and/ordevice embodiments, and/or combinations thereof, to measuring andevaluating a signal generated by a device under test (DUT).

In some embodiments, a system may be configured to capture an acousticsignal generated by a reference speaker calibrated at a first poweroutput level and store the acoustic signal generated at the first poweroutput level as a first reference signal. Similarly, the system may beconfigured to capture an acoustic signal generated by the referencespeaker calibrated at a second power output level and store the acousticsignal generated at the second power output level as a second referencesignal. The system may also be configured to capture a first test signaland a second test signal from a device under test at each respectivepower output level, process the first and second test signals to extractindividual frequency bins for each signal, and compare the first andsecond test signals to a respective one of the first and secondreference signals. For each comparison, the system may be configured togenerate a report indicating a performance grade of the device undertest. For example, the report may include a graphical illustration ofthe performance grade of the device under test. The performance grademay be derived from a sinusoidal, frequency based step sweep comparisonof the test signals to the reference signals at each power output level.

FIG. 1 illustrates a testing environment for measuring and evaluating asignal generated by a device under test (DUT). Referring to FIG. 1, thetesting environment 100 may include a testing device 102, an audiocapturing device 104, and a DUT 106 having one or more DUT speakers 108.The testing device 102 and the audio capturing device 104 may be coupledto each other using either a wired connection or a wireless connection,as should be understood by those of ordinary skill in the art. Forexample, the testing device 102 and the audio capturing device 104 maycommunicate via a communication network(s) 110. The communicationnetwork 110 may include any or all of a wired and/or wireless privatenetwork, personal area network (PAN), Local-Area Network (LAN), aWide-Area Network (WAN), or the Internet. The audio capturing device 104may any well-known audio capturing device, such as, but not limited to,a microphone, a vibrometer, a laser, or the like. The testing device 102may be a computing device, such as the computer system 400 illustratedin FIG. 4 discussed in greater detail below. In some embodiments, theprocesses described herein performed by the testing device 102 may beperformed using a processor, e.g., a processor 404 as shown in FIG. 4.

The DUT 106 may be, without limitation, a media player, television, awireless device, a smartphone, a tablet computer, a laptop/mobilecomputer, a handheld computer, a server computer, an in-appliancedevice, Internet of Things (IoT) device, streaming media player, a gameconsole, and/or an audio/video receiver. In some embodiments, thespeakers 108 may be different types of audio devices. For example, thespeakers 108 may be, without limitation, a combination of one or moredifferent types of speakers, such as full-range drivers, subwoofers,woofers, mid-range drivers, tweeters, sound bars, and/or coaxialdrivers, to name just some examples. It should be understood by those ofordinary skill in the arts that each of the speakers 108 may be designedto produce sound at different frequencies. For example, a tweeter may bedesigned to produce sound at high audio frequencies, e.g., 2,000 Hz to20,000 Hz, whereas subwoofers and woofers may be designed to producesound at low audio frequencies, e.g., 40 Hz up to 500 Hz. As such, eachspeaker 108 may be designed to produce different features of an audiosignal, e.g., tweeters may be designed to produce more treble, whereaswoofers and sub-woofers may be designed to produce more bass andsub-bass, respectively.

To measure and evaluate a test signal output by the DUT speaker 108, thetesting device 102 may be configured to compare the test signal to areference signal output by a reference speaker. More specifically, asillustrated in FIG. 5A, an ideal acoustic signal may be represented by asinusoidal wave having a smooth curve in the time domain, and asillustrated in FIG. 5B, the ideal acoustic signal may have a single peakat the fundamental frequency of the acoustic signal in the spectraldomain. In other words, an ideal acoustic signal is a perfect sinusoidalwave that is free of deformations in the time domain and with a singlepeak in the spectral domain.

In practical implementations, acoustic signals generated by speakershave imperfect sinusoidal waves in the time domain and additional peaksat different frequencies in addition to the peak at the fundamentalfrequency in the spectral domain. However, some high quality speakersmay generate an acoustic signal having near perfect sinusoidal waves inthe time domain and a limited number of peaks at different frequenciesin the spectral domain. For example, as respectively illustrated inFIGS. 6A-6B, an acoustic signal from the reference speaker may include alimited number of imperfections in the time domain and a limited numberof additional peaks, e.g., five peaks, in the spectral domain. As such,the acoustic signal from the reference speaker may be used as areference signal given its high level of performance relative to theideal acoustic signal. In contrast to the reference speaker, asrespectively illustrated in FIGS. 6C-6D, in the time domain, an acousticsignal from a poor quality speaker may have jagged curve rather a smoothcurve, and in the spectral domain, the signal may have a large number ofadditional peaks.

In some embodiments, the testing device 102 may capture the referencesignal from the reference speaker using the audio capturing device 104,slice the reference signal into a plurality of reference audio filesbased on a plurality of frequency bins, and store each of the pluralityof reference audio files in a memory, e.g., main memory 408 or secondarymemory 410 of FIG. 4. The audio files may be, for example, anyuncompressed audio format, such as, but not limited to, .WAV, .AIFF, .AUor .PCM. It should be understood by those of ordinary skill in the artsthat these are merely example types of audio files and that other typesof audio files are further contemplated in accordance with aspects ofthe present disclosure. For example, the audio files may also be anyformat with lossless compression or lossy compression, as should beunderstood by those of ordinary skill in the arts. In some embodiments,the plurality of reference audio files may be a snippet, e.g., 1 second,of the reference signal.

For example, the reference speaker may playback media content having anaudio component, such as, but not limited to, a movie, a televisionshow, music, or the like, and the audio capturing device 104 may capturethe audio content while placed a distance, e.g., 20 centimeters, fromthe reference speaker when capturing the reference signal. Oncecaptured, the reference signal may be sliced into the plurality ofreference audio files based on the plurality of frequency bins, witheach reference audio file being based on one of the plurality offrequency bins. In some embodiments, the plurality of frequency bins maybe between 50 Hz and 16 kHz. For example, the plurality of frequencybins may include frequency bins at 50 Hz, 100 Hz, 200 Hz, 300 Hz, 400Hz, 500 Hz, 600 Hz, 700 Hz, 800 Hz, 900 Hz, 1000 Hz, 2000 Hz, 4000 Hz,8000 Hz, and 16000 Hz. It should be understood by those of ordinaryskill in the arts that these are merely examples of frequencies that maybe used as the plurality of frequency bins and that other frequency binsare further contemplated in accordance with aspects of the presentdisclosure. In some embodiments, the reference signal may be generatedat, for example, −10 dBFS in order to utilize a full dynamic range ofthe reference speaker.

In some embodiments, the reference signal may be captured at a pluralityof a plurality of power output levels (i.e., sound pressure levels(SPLs)). For example, the plurality of power output levels may include amaximum power output level and a moderate power output level. Themaximum power output level may be, for example, a maximum output Max_dBof the reference speaker measured in decibels. The moderate power outputlevel may be, for example, an average of the maximum output Max_DB and aminimum output Min_dB of the reference speaker measured in decibels,i.e., (Max_DB−Min_dB)/2. In further embodiments, the moderate poweroutput level may be the average of the maximum output Max_DB and theminimum output Min_dB plus an offset coefficient offset_DB, e.g.,(Max_dB−Min_dB)/2+offset_DB. The offset coefficient may be, for example,9 dB. In some embodiments, the reference signal may be sliced into theplurality of reference audio files at each power output level.

After the reference audio files for each power output level are storedon the memory of the testing device 102, the DUT 106 may playback thesame media content as the reference speaker via the DUT speaker 108, andthe audio capturing device 104 may capture an acoustic signal generatedby the DUT speaker 108, i.e., a test signal. In some embodiments, theDUT speaker 108 may be tested under the same conditions as theconditions used to capture the reference signal. For example, the DUTspeaker 108 may be placed at the same distance from the audio capturingdevice 104, e.g., 20 centimeters, as the reference speaker, and capturedusing the same audio capturing device 104 as that used to capture thereference signal. By testing the DUT speaker 108 under the sameconditions as the reference speaker, the present disclosure ensures thatthe measurement and evaluation the acoustic signal generated by the DUTspeaker 108 is not influenced by inconsistencies caused by an externalenvironment. For example, placing the audio capturing device 104 at adifferent distance for the reference speaker and the DUT speaker 108 mayaffect the signal strength of one of the signals. Similarly, using adifferent audio capturing devices for capturing each of the signals mayintroduce differences between the two signals caused by the quality ofthe audio capturing devices, rather than the speakers themselves.

Like the reference signal, the test signal may be sliced into aplurality of test audio files based on the plurality of frequency bins,with each test audio file being based on one of the plurality offrequency bins. In some embodiments, the plurality of frequency bins maybe between 50 Hz and 16 kHz. For example, the plurality of frequencybins may include frequency bins at 50 Hz, 100 Hz, 200 Hz, 300 Hz, 400Hz, 500 Hz, 600 Hz, 700 Hz, 800 Hz, 900 Hz, 1000 Hz, 2000 Hz, 4000 Hz,8000 Hz, and 16000 Hz. It should be understood by those of ordinaryskill in the arts that these are merely examples of frequencies that maybe used as the plurality of frequency bins and that other frequency binsare further contemplated in accordance with aspects of the presentdisclosure. In some embodiments, the test signal may be generated at,for example, −10 dBFS in order to utilize a full dynamic range of theDUT speaker 108. In some embodiments, the plurality of test audio filesmay be a snippet, e.g., 1 second, of the test signal.

In some embodiments, the test signal may be captured at the plurality ofpower output levels (i.e., sound pressure levels (SPLs)). For example,the plurality of power output levels may include a maximum power outputlevel and a moderate power output level. The maximum power output levelmay be, for example, a maximum output Max_dB of the DUT speaker 108measured in decibels. The moderate power output level may be, forexample, an average of the maximum output Max_DB and a minimum outputMin_dB of the DUT speaker 108 measured in decibels, i.e.,(Max_DB−Min_dB)/2. In further embodiments, the moderate power outputlevel may be the average of the maximum output Max_DB and the minimumoutput Min_dB plus an offset coefficient offset_DB. e.g.,(Max_dB−Min_dB)/2+offset_DB. The offset coefficient may be, for example,9 dB. In some embodiments, the test signal may be sliced into theplurality of test audio files at each power output level.

The testing device 102 may then compare each test signal to thereference signal at each power output level. For example, the comparisonmay include comparing a test audio file to a corresponding one of thereference audio files at each power output level. For example, for eachpower output level, the test audio file at the 50 Hz frequency bin maybe compared to the reference audio file at the 50 Hz frequency bin, thetest audio file at the 100 Hz frequency bin may be compared to thereference audio file at the 100 Hz frequency bin, the test audio file atthe 200 Hz frequency bin may be compared to the reference audio file atthe 200 Hz frequency bin, and so on and so forth. That is, two sets offiles are compared to another—1) at the maximum power output level, thetest audio files are compared to the reference audio files and 2) at themoderate power output level, the test audio files are compared to thereference audio files.

In some embodiments, the comparison may include calculating a distancebetween the test signal and the reference signal at each frequency bin.This may be achieved using an open source library to calculate amel-frequency cepstral coefficient (MFCC) difference metric, e.g., aspectral difference, as should be understood by those of ordinary skillin the art. For example, the MFCC difference may be based on a pluralityof vectors determined from the comparison of the test signal and thereference signal. The MFCC difference metric may be implemented usingany programming language, procedural, functional, or object-oriented.Non-limiting examples include C, C++, C #, Objective-C, Java. Swift, Go,Ruby, Perl, Python, JavaScript, WebAssembly, or virtually any otherlanguage, with any other libraries or schemas, in any kind of framework,runtime environment, virtual machine, interpreter, stack, engine, orsimilar mechanism, including but not limited to Node.js, V8, Knockout,jQuery, Dojo, Dijit, OpenUI5, AngularJS, Express.js, Backbone.js.Ember.js, DHTMLX, Vue, React, Electron, and so on, among many othernon-limiting examples.

In some embodiments, the distance between the test signal and thereference signal may be used to grade the DUT speaker 108. In this way,the testing device 102 may generate a performance score of the DUTspeaker 108 at each frequency bin for each of the plurality of poweroutput levels. The performance score may be a measure of a difference ina total harmonic distortion between the reference signal and the testsignal for each frequency bin. For example, the distance between thetest signal and the reference signal may be measured on a scale from0-300, with 0 indicating no distance between the signals and 300indicating a significant distance between the signals.

The distance may be compared to a plurality of threshold values to gradethe DUT speaker 108. For example, when the distance is greater than afirst threshold value, the DUT speaker 108 may be given a first grade atthe given frequency bin. In some embodiments, the DUT 106 may beadjusted using a digital signal processing (DSP), as should beunderstood by those of ordinary skill in the art. As another example,when the distance is less than the first threshold value and greaterthan a second threshold value, the DUT speaker 108 may be given a secondgrade at the given frequency bin. Even further, when the distance isless than the second threshold value, the DUT speaker 108 may be given athird grade at the given frequency bin. In some embodiments, the firstgrade may be a failing grade, thereby indicating that the DUT 106 needsto be adjusted at such frequency. In contrast, the second and thirdgrades may be passing grades. In some embodiments, an overall score fordetermining whether the DUT speaker 108 passes may be based on anaverage of the distances at each frequency bin of the plurality offrequency bins. The overall score may likewise be compared to theaforementioned thresholds and the DUT speaker 108 may be graded in thesame manner.

In some embodiments, the DUT speaker 108 may be tested on achannel-by-channel basis. For example, for a stereo speaker, theprocesses described herein may be performed with respect to the both theleft and right channels.

The testing device 102 may generate a report indicating the performancescore. For example, as illustrated in FIG. 7, the report may include aperformance graph of the test signal at each frequency bin. As anotherexample illustrated in FIGS. 8 and 9, the performance graph may alsoinclude distance between the test signal and the reference signal ateach frequency bin. In some embodiments, the distance illustrated on theperformance graph may be colored to indicate whether the performancescore received a first, second, or third grade. For example, the firstgrade may be colored red, the second grade may be colored yellow, andthe third grade may be colored green. As further illustrated in FIGS. 8and 9, the report may include a summary portion indicating the overallperformance of the DUT speaker 108. For example, the summary portion mayindicate the power output level of the DUT speaker 108, whether the DUTspeaker 108 passed (see, e.g., FIG. 8) or failed (see, e.g., FIG. 9), anaverage distance, and any frequencies at which the performance of theDUT speaker 108 may be improved, e.g., 100 Hz bin as shown in FIG. 8.

FIG. 2 is a block diagram of an example embodiment of a speaker 200,e.g., the speaker 108 of FIG. 1. The speaker 200 may comprise aprocessor 206, a non-transitory, tangible computer readable memory (CRM)208, one or more amplifiers 210, a speaker control module 218 forreceiving user commands via one or more controls (e.g., buttons and/or aremote control interface), a power supply 220, or more filters 228(e.g., the filters 120), transducers 212, and a speaker cabinet 222 toenclose components of the speaker 200.

The communication interface(s) 202 may include one or more interfacesand hardware components for enabling communication with various otherdevices. For example, communication interface(s) 202 facilitatecommunication through one or more of the Internet, cellular networks,and wireless networks (e.g., Wi-Fi, cellular). The non-transitory,tangible computer readable memory (CRM) 208 may be used to store anynumber of functional components that are executable by the processor206. In many implementations, these functional components compriseinstructions or programs that are executable by the processors and that,when executed, specifically configure the one or more processors 206 toperform the actions attributed above to the speakers (e.g., the speaker108). In addition, the non-transitory, tangible computer readable memory208 stores data used for performing the operations described herein.

The processor 206 may select which portion of the content will beprocessed. In some embodiments, in a stereo mode, for example, thespeaker 200 processes either the left stereophonic channel or rightstereophonic channel. In a surround sound mode, the speaker 200 selectsa signal to process from among the multiple channels. The selection ofthe playback mode (e.g., stereo mode, mono mode, surround sound mode)may be performed via the speaker control module 218. In someembodiments, the filters 228 modify the content to determine thefrequencies of the content that are reproduced by the speaker 200 inaccordance with the filter settings 232. This may be done by performingcrossover, phase matching, and time alignment filtering function in adigital implementation. In some examples, the filters 228 may includeFIR or IIR filters that implement a crossover filtering technique.

The output of the processor 206 may be a set of filtered digital audiosignals, one for each of the transducers 212. These signals may bedirected to the inputs of digital amplifiers, which generate high poweroutput signals that drive the speaker transducers 212 to produce anoptimal and/or improved reproduction of the content in concert with oneor more other speakers having different performance capabilities inaccordance with the present invention.

FIG. 3 illustrates an example method for measuring and evaluating asignal generated by a device under test (DUT).

For example, at 305, a testing device (e.g., testing device 102 ofFIG. 1) may capture a test signal from the DUT (e.g., DUT 106 of FIG.1).

At 310, the testing device (e.g., testing device 102 of FIG. 1) mayslice the test signal into a plurality of test audio files based on aplurality of frequency bins.

At 315, at each frequency bin, the testing device (e.g., testing device102 of FIG. 1) may compare each of the plurality of test audio files toa corresponding reference audio file from among a plurality of referenceaudio files. The plurality of reference audio files may be associatedwith a reference signal.

At 320, the testing device (e.g., testing device 102 of FIG. 1) maycalculate a performance score of the device under test based on thecomparisons.

Example Computer System

Various embodiments can be implemented, for example, using one or morewell-known computer systems, such as computer system 400 shown in FIG.4. Computer system 400 can be any well-known computer capable ofperforming the functions described herein, such as computers availablefrom International Business Machines, Apple, Sun, HP, Dell, Sony,Toshiba, etc.

Computer system 400 includes one or more processors (also called centralprocessing units, or CPUs), such as a processor 404. Processor 404 isconnected to a communication infrastructure or bus 402.

Computer system 400 also includes user input/output device(s) 432, suchas monitors, keyboards, pointing devices, etc., which communicate withcommunication infrastructure 402 through user input/output interface(s)430.

Computer system 400 also includes a main or primary memory 408, such asrandom access memory (RAM). Main memory 408 may include one or morelevels of cache. Main memory 408 has stored therein control logic (i.e.,computer software) and/or data.

Computer system 400 may also include one or more secondary storagedevices or memory 410. Secondary memory 410 may include, for example, ahard disk drive 412 and/or a removable storage device or drive 414.Removable storage drive 414 may be a floppy disk drive, a magnetic tapedrive, a compact disk drive, an optical storage device, tape backupdevice, and/or any other storage device/drive.

Removable storage drive 414 and interface 420 may interact with aremovable storage units 416, 418, respectively. Removable storage units416, 418 includes a computer usable or readable storage device havingstored thereon computer software (control logic) and/or data. Removablestorage units 416, 418 may be a floppy disk, magnetic tape, compactdisk, DVD, optical storage disk, and/any other computer data storagedevice. Removable storage drive 414 reads from and/or writes toremovable storage unit 416 in a well-known manner.

According to an exemplary embodiment, secondary memory 410 may includeother means, instrumentalities or other approaches for allowing computerprograms and/or other instructions and/or data to be accessed bycomputer system 400. Such means, instrumentalities or other approachesmay include, for example, a removable storage drive 414 and an interface420. Examples of the removable storage drive 414 and the interface 420may include a program cartridge and cartridge interface (such as thatfound in video game devices), a removable memory chip (such as an EPROMor PROM) and associated socket, a memory stick and USB port, a memorycard and associated memory card slot, and/or any other removable storageunit and associated interface.

Computer system 400 may further include a communication or networkinterface 424. Communication interface 424 enables computer system 400to communicate and interact with any combination of remote devices,remote networks, remote entities, etc. (individually and collectivelyreferenced by reference number 428). For example, communicationinterface 424 may allow computer system 400 to communicate with remotedevices 428 over communications path 426, which may be wired and/orwireless, and which may include any combination of LANs. WANs, theInternet, etc. Control logic and/or data may be transmitted to and fromcomputer system 400 via communication path 426.

In an embodiment, a tangible apparatus or article of manufacturecomprising a tangible computer useable or readable medium having controllogic (software) stored thereon is also referred to herein as a computerprogram product or program storage device. This includes, but is notlimited to, computer system 400, main memory 408, secondary memory 410,and removable storage units 416, 418, as well as tangible articles ofmanufacture embodying any combination of the foregoing. Such controllogic, when executed by one or more data processing devices (such ascomputer system 400), causes such data processing devices to operate asdescribed herein.

Based on the teachings contained in this disclosure, it will be apparentto persons skilled in the relevant art(s) how to make and useembodiments of this disclosure using data processing devices, computersystems and/or computer architectures other than that shown in FIG. 4.In particular, embodiments can operate with software, hardware, and/oroperating system implementations other than those described herein.

It is to be appreciated that the Detailed Description section, and notany other section, is intended to be used to interpret the claims. Othersections can set forth one or more but not all exemplary embodiments ascontemplated by the inventor(s), and thus, are not intended to limitthis disclosure or the appended claims in any way.

While this disclosure describes exemplary embodiments for exemplaryfields and applications, it should be understood that the disclosure isnot limited thereto. Other embodiments and modifications thereto arepossible, and are within the scope and spirit of this disclosure. Forexample, and without limiting the generality of this paragraph,embodiments are not limited to the software, hardware, firmware, and/orentities illustrated in the figures and/or described herein. Further,embodiments (whether or not explicitly described herein) havesignificant utility to fields and applications beyond the examplesdescribed herein.

Embodiments have been described herein with the aid of functionalbuilding blocks illustrating the implementation of specified functionsand relationships thereof. The boundaries of these functional buildingblocks have been arbitrarily defined herein for the convenience of thedescription. Alternate boundaries can be defined as long as thespecified functions and relationships (or equivalents thereof) areappropriately performed. Also, alternative embodiments can performfunctional blocks, steps, operations, methods, etc. using orderingsdifferent than those described herein.

References herein to “one embodiment,” “an embodiment,” “an exampleembodiment,” or similar phrases, indicate that the embodiment describedcan include a particular feature, structure, or characteristic, butevery embodiment can not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a particular feature,structure, or characteristic is described in connection with anembodiment, it would be within the knowledge of persons skilled in therelevant art(s) to incorporate such feature, structure, orcharacteristic into other embodiments whether or not explicitlymentioned or described herein. Additionally, some embodiments can bedescribed using the expression “coupled” and “connected” along withtheir derivatives. These terms are not necessarily intended as synonymsfor each other. For example, some embodiments can be described using theterms “connected” and/or “coupled” to indicate that two or more elementsare in direct physical or electrical contact with each other. The term“coupled.” however, can also mean that two or more elements are not indirect contact with each other, but yet still co-operate or interactwith each other.

The breadth and scope of this disclosure should not be limited by any ofthe above-described exemplary embodiments, but should be defined only inaccordance with the following claims and their equivalents.

What is claimed is:
 1. A method for testing a device, comprising:determining a first performance score by comparing a first test audiofile and a first reference audio file both containing audio signalswithin a first frequency bin; comparing the first performance score witha first set of threshold values to determine a first grade for one ormore speakers of a device under test (DUT) in the first frequency bin;determining a second performance score by comparing a second test audiofile and a second reference audio file both containing audio signalswithin a second frequency bin; comparing a second set of thresholdvalues with the second performance score to determine a second grade forthe one or more speakers in the second frequency bin; and determining anoverall score for the one or more speakers based on the firstperformance score, the second performance score, the first grade, andthe second grade, wherein the first test audio file and the second testaudio file are generated by the one or more speakers from playing mediacontent, and the first reference audio file and the second referenceaudio file are generated by a reference speaker from playing the samemedia content, and wherein the first performance score indicates aharmonic distortion between the first test audio file and the firstreference audio file.
 2. The method of claim 1, wherein the firstperformance score and the second performance score are based on amel-frequency cepstral coefficient (MFCC) difference metric.
 3. Themethod of claim 1, wherein the first set of threshold values includes atleast a pass grade and a failure grade.
 4. The method of claim 1,wherein the first frequency bin includes a frequency bin at about 50 Hz,100 Hz, 200 Hz, 300 Hz, 400 Hz, 500 Hz, 600 Hz, 700 Hz, 800 Hz, 900 Hz,1000 Hz, 2000 Hz, 4000 Hz, 8000 Hz, or 16000 Hz.
 5. The method of claim1, wherein the first test audio file includes an audio file in anuncompressed audio format, a .WAV format audio file, a .AIFF formataudio file, a .AU format audio file, or a .PCM format audio file.
 6. Themethod of claim 1, wherein the one or more speakers include a full-rangedriver speaker, a subwoofer speaker, a woofer speaker, a mid-rangedriver speaker, a tweeter speaker, a sound bar speaker, or a coaxialdriver.
 7. The method of claim 1, wherein the DUT includes a mediaplayer, a television, a wireless device, a smartphone, a tabletcomputer, a laptop/mobile computer, a handheld computer, a servercomputer, an in-appliance device, an Internet of Things (IoT) device, astreaming media player, a game console, an audio receiver, or a videoreceiver.
 8. The method of claim 1, wherein the first test audio fileand the first reference audio file are generated at a first power outputlevel, and the second test audio file and the second reference audiofile are generated at a second power output level.
 9. The method ofclaim 1, wherein the one or more speakers include a stereo speaker, thefirst test audio file and the first reference audio file are generatedfor a left channel, and the second test audio file and the secondreference audio file are generated for a right channel.
 10. The methodof claim 1, wherein the one or more speakers play the media content togenerate the first test audio file and the first reference audio file ata stereo mode, a mono mode, or a surround sound mode.
 11. The method ofclaim 1, wherein the one or more speakers include a first speaker toproduce audio signals with treble signals, and a second speaker toproduce audio signals with bass and sub-bass signals.
 12. The method ofclaim 1, wherein the media content includes a movie, a television show,or music.
 13. A non-transitory tangible computer-readable medium havinginstructions stored thereon that, when executed by at least onecomputing device, cause the at least one computing device to performoperations comprising: determining a first performance score bycomparing a first test audio file and a first reference audio file bothcontaining audio signals within a first frequency bin; comparing thefirst performance score with a first set of threshold values todetermine a first grade for one or more speakers of a device under test(DUT) in the first frequency bin; determining a second performance scoreby comparing a second test audio file and a second reference audio fileboth containing audio signals within a second frequency bin; comparing asecond set of threshold values with the second performance score todetermine a second grade for the one or more speakers in the secondfrequency bin; and determining an overall score for the one or morespeakers based on the first performance score, the second performancescore, the first grade, and the second grade, wherein the first testaudio file and the second test audio file are generated by the one ormore speakers from playing media content, and the first reference audiofile and the second reference audio file are generated by a referencespeaker from playing the same media content, and wherein the firstperformance score indicates a harmonic distortion between the first testaudio file and the first reference audio file.
 14. The non-transitorytangible computer-readable medium of claim 13, wherein the firstperformance score and the second performance score are based on amel-frequency cepstral coefficient (MFCC) difference metric.
 15. Thenon-transitory tangible computer-readable medium of claim 13, whereinthe one or more speakers include a full-range driver speaker, asubwoofer speaker, a woofer speaker, a mid-range driver speaker, atweeter speaker, a sound bar speaker, or a coaxial driver.
 16. Thenon-transitory tangible computer-readable medium of claim 13, whereinthe first test audio file and the first reference audio file aregenerated at a first power output level, and the second test audio fileand the second reference audio file are generated at a second poweroutput level.
 17. The non-transitory tangible computer-readable mediumof claim 13, wherein the one or more speakers include a stereo speaker,the first test audio file and the first reference audio file aregenerated for a left channel, and the second test audio file and thesecond reference audio file are generated for a right channel.
 18. Thenon-transitory tangible computer-readable medium of claim 13, whereinthe one or more speakers include a first speaker to produce audiosignals with treble signals, and a second speaker to produce audiosignals with bass and sub-bass signals.
 19. A device comprising: amemory storing a first test audio file, a first reference audio file, asecond test audio file, and a second reference audio file; a processorcoupled to the memory and configured to perform operations comprising:determining a first performance score by comparing the first test audiofile and the first reference audio file both containing audio signalswithin a first frequency bin; comparing the first performance score witha first set of threshold values to determine a first grade for one ormore speakers of a device under test (DUT) in the first frequency bin;determining a second performance score by comparing the second testaudio file and the second reference audio file both containing audiosignals within a second frequency bin; comparing a second set ofthreshold values with the second performance score to determine a secondgrade for the one or more speakers in the second frequency bin; anddetermining an overall score for the one or more speakers based on thefirst performance score, the second performance score, the first grade,and the second grade, wherein the first test audio file and the secondtest audio file are generated by the one or more speakers from playingmedia content, and the first reference audio file and the secondreference audio file are generated by a reference speaker from playingthe same media content, and wherein the first performance scoreindicates a harmonic distortion between the first test audio file andthe first reference audio file.
 20. The device of claim 19, wherein theone or more speakers include a full-range driver speaker, a subwooferspeaker, a woofer speaker, a mid-range driver speaker, a tweeterspeaker, a sound bar speaker, or a coaxial driver.
 21. A method fortesting a device, comprising: determining a performance score bycomparing a test audio file and a reference audio file both containingaudio signals within a frequency bin; comparing the performance scorewith a set of threshold values to determine a grade for one or morespeakers of a device under test (DUT) in the frequency bin; anddetermining an overall score for the one or more speakers based on theperformance score or the grade, wherein the test audio file is generatedby the one or more speakers from playing media content, and thereference audio file is generated by a reference speaker from playingthe same media content, and wherein the performance score indicates aharmonic distortion between the test audio file and the reference audiofile.